Based on their presentation of antigenic epitopes and secretion of various cytokines and chemokines which initiate and/or enhance many cell types, antigen-presenting cells (APC) and dendritic cells (DC) are known for their ability to alter and direct different immunological responses and thus induce a phenomenon of B and T cell plasticity. Similarly to multi-potential progenitor cells, APC and DC can be located in different tissues such as the lymph nodes and the bone marrow (BM) or in the circulation. Likewise, DC in different stages of maturity can be found in a variety of tissues.
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